chapter 2 Flashcards
chromatin
is the stainable material in a cell nucleus: DNA and proteins
Histones and Nonhistones
two major types of proteins associated with DNA in chromatin.
Topoisomerases
The amount and type of DNA supercoiled is controlled by these enzymes that are found in all organisms.
Plasmids
autonomously replicating small chromosomes not essential to the life of the cell.
Different DNA structures are ________
A-DNA, B-DNA, AND Z-DNA
In the cell the functional forms of RNA are________, and how many strands to they have?
mRNA, tRNA, rRNA (ribosomal RNA), snRNA (small nuclear), and miRNA (micro), and they are all single stranded molecules.
Many monomers make up _______ and _______ are called _______
DNA, & RNA…… nucleotides
nucleotides consist of ________
a sugar (pentose), a phosphate group, and a nitrogenous base (contains a nitrogen)
The pentose sugar for DNA is______ and the pentose sugar for RNA is________
deoxyribose, and ribose
There are two classes of bases which are _______
purines, and pyrimidines
purines are nine membered double rings and include _______
adenine, and guanine
pyrimidines are six membered single rings and include_______
thymine, cytosine, and uracil
The combination of a sugar and a base is called______
nucleoside.
Many nucleotides linked together are named_______
polynucleotides and make up DNA or RNA.
The bonds between bases are called ______ and they follow a ____ to____ sequence.
phosphodiester bonds. 5 to 3 prime.
The full amount of genetic material found in a virus, a prokaryotic cell, a eukaryotic organelle, or in one haploid set of a haploid organism’s chromosomes is ________.
genome
There are two types of supercoiling which are ______ and ______ what does each one do
positive and negative. positive adds another base turn, negative removes another base turn.
Usually all proteins associated with DNA and have a net negative charge are______ ________
nonhistones.
The basic structural units of eukaryotic chromatin are ________
nucleosomes
There are five main histones_______
H1, H2A, H2B, H3, H4
Which has a higher C-value plants, animals, or humans?
Plants, then humans, then animals.
A specific set of sequences at the end of a linear chromosome, stabilizes the chromosome and is required for replication is called________
telomere
Is the region of a chromosome containing DNA sequences to which mitotic and meiotic spindle fibers attach.
centromere
In the 1930’s - 1940’s They lysed (broke open) III-s cells with a detergent created the Avery transformation experiment.
Oswald T. Avery, Colin M. Macleod, and Maclyn McCarty.
In 1928 British medical officer was working with streptococcus pneumoniae. Discovered virulent strain is smooth and has a polysaccharide coat non-virulent strains are rough.
Fredrick Griffith, Griffiths transformation experiment
Threadlike structures found in nuclei carriers of hereditary information.
chromosomes
In 1869 swiss biochemist isolated substance from white blood cells of pus in used bandages from the crimean war, and discovered nucleic acid.
Friedrich Miescher
In 1953 they published a paper that provided more evidence that DNA was genetic material.
Alfred D. Hershey, Martha Chase
The phosphate group attaches to which carbon on a pentose ring?
The 5’
On one end there is a phosphate group attached to the 5’ carbon and on the other end is an OH group attached to the 3’ carbon there making _______ chains ______.
polynucleotide, polar
In 1953 they proposed a model for the physical and chemical structure of the DNA molecule.
James D. Watson, Francis H.C. Crick
Performed base composition studies using x-ray diffraction.
Erwin Chargoff, Rosalin Franklin, and Maurice H.F. Wilkins
DNA is made up of ________ (sugar), _______ (purine), _________(pyrimidine), and _________ ________. where is the hydrogen atom attached.
deoxyribose nucleic acid, adinine (A), guanine (g), cytosine (C), Thymine (T), and phosphate group. the #2 carbon.
RNA is made up of ________ (sugar), _______ (purine), _________(pyrimidine), and _________ ________. where is the hydroxyl group attached.
ribose, adinine, guanine, cytosine, uracil, phosphate group, and the 2’ carbon.
DNA sequence that is present in one to a few copies in the genome.
unique-sequence DNA
DNA present in a few to about 10^5 copies in the genome.
moderately repetitive
DNA present in about 10^5 to 10^7 copies in the genome.
highly repetitive
The greatest amount of tandemly repeated DNA is associated with the ________ and the ________
centromeres and telomeres.
